You will probably get much more interest in a fly swap during the colder off-season months. From now until late fall, most of us are too busy fishing to participate in swaps. And what we are tying is most likely for personal use to replenish certain hot flies lost during fishing.
If you check the archives, you'll notice that the swaps really are more of a winter thing. I'm not discouraging you from trying, but don't be disappointed if participation is low or nil right now.